package design;

public class Singleton_04内部类线程安全 {

    private static class SingletonHolder {
        private static Singleton_04内部类线程安全 instance = new Singleton_04内部类线程安全();
    }

    private Singleton_04内部类线程安全() {
    }

    public static Singleton_04内部类线程安全 getInstance() {
        return SingletonHolder.instance;
    }

}
